1. Field of the Invention
This invention relates in general to certain new and useful improvements in pay telephones and, more particularly, to pay telephones which can be self-supporting in a stand-alone condition or wall mounted and in which operating components of the pay telephone are easily mounted within an outer housing and easily serviceable in that housing.
2. Brief Description of the Related Art
Currency operated telephones, that is, telephones which operate upon the introduction of a currency, namely, so-called "pay telephones", are widely used and have been effectively operated by telephone companies for more than fifty years. These telephones typically operate on the basis of enabling the generation of dual tone multi-frequency dialing signals or enabling the completion of a telephone call when a proper amount of a currency (either paper currency or coin currency) has been introduced into the telephone. For this purpose, the telephone is equipped with a coin mechanism or a paper currency mechanism, such as a so-called "dollar bill acceptor". These telephones are also enabled by a telephone card via a card reading device.
During this period of time, many advances have been made in these pay telephones. The advances which have been introduced into these telephones are largely electronic type advances and include, for example, improvements in solid state circuitry designs, coin mechanisms, and use of dual tone multi-frequency dialing, as opposed to the voltage modulated digital signals obtained with rotary dial telephones. However, in large measure, the outer housing of the pay telephone has changed very little. The outer housings are typically formed of a steel box-like construction and are quite rigid and durable, as they must be, to preclude pilfering and theft of introduced currency. Nevertheless, the same box-like appearance which had started almost fifty years ago still obtains today, although with some relatively insignificant modifications.
All commercially available pay telephones are wall mounted telephones, or at least telephones fixedly mounted within and to walls of telephone stalls or walls or other supporting structure of telephone stands. Moreover, because of the box-like construction, these telephones are not capable of being mounted in both a wall suspended position and in a stand-alone position, since the center of gravity of the conventional wall mounted pay telephones causes them to tip over or become unstable if minimal pressure is applied to the upper dialing keys when the phone is in a free standing position. Furthermore, the face plate instructions, would not be readily readable in both such positions.
In addition to the foregoing, the operating components of the commercially available and proposed pay telephones, such as the currency acceptor, the electronic circuit board, the coin return mechanism, are all individual components with each physically mounted within the outer housing. Thereafter, various means for connecting these individual components together by various electrical cables, duct work and the like, is employed.
Furthermore, in these various commercially available and proposed pay telephones, there are usually several individual circuit boards which are employed and which are connected together. The key pad was connected to a digital dialing mechanism, such as a touch tone generator by means of electrical cables, and the dialing mechanism was connected to a processor by additional electrical cables. The actual telephone circuitry incorporated in those one or more circuit boards were connected to the hand set by additional electrical conductors. As a result of this type of construction, the actual assembly of pay telephones was labor intensive and, hence, the overall cost thereof was substantial.
Due to the complexity of the construction of the conventional pay telephone, maintenance or servicing was also labor intensive. In order to obtain access to one component, various disconnections had to be made. In addition, since all of the electronics was not incorporated on one circuit board, testing for any electronic failure became a difficult problem.
These conventional pay telephones with a heavy box-like construction, were usually constructed using a drawn metal process which is both expensive and requires a substantial amount of material to produce. Admittedly, they had a relatively strong theft-proof outer housing. However, this construction comes with a relatively high cost of construction and a substantial weight which also required a more sturdy supporting structure for mounting the telephone to that supporting structure. Thus, the presently existing pay telephones are costly, cumbersome, difficult to service and, even more so, relatively unattractive and certainly not capable of being moved, as is a private telephone system.
The prior art is replete with numerous U.S. patent references showing conventional pay telephone constructions. For example, the McGough U.S. Pat. No. 4,938,547 and the McGough U.S. Pat. No. 4,940,296 both disclose a conventional box-like housing which is only adapted for wall mounted construction. Moreover, it can be observed that the housing is complex and requires numerous parts for assembly.
U.S. Pat. No. 4,747,134 to Holland shows a conventional hook switch assembly which can be used in pay telephones and, again, relies upon a complex mechanism involving numerous electrical components and/or electromechanical components. This type of hook switch mechanism is expensive and subject to potential failure.
U.S. Pat. No. 3,846,594 to Morrell also discloses a conventional box-like and wall mounted telephone construction. Although the telephone housing in the Morrell patent is similar in appearance to the outer housing in each of the aforesaid McGough patents, it provides a somewhat different means for securing the front closure section to the body of the housing. Again, this Morrell patent also discloses the complexity of installing the numerous operating components.
U.S. Pat. No. 4,974,257 to Ibanez, et al further discloses a modular public telephone which uses a pair of telephone housings, one for containing the telephone operating mechanism and the other for receiving currency and includes, for example, a coin box. Again, the Ibanez patent discloses the complexity of the overall pay telephone construction and the use of separate individual components which must be connected together. Ibanez also discloses a touch tone pad arrangement for use on the front of the housing and the complexity of construction and integration with the other operating components of the pay telephone.